Composition to completely or partially replace ball clay in ceramics, method of making, and use thereof

ABSTRACT

A composition comprises at least one form of attapulgite present in a solid weight fraction amount ranging from 0.25% to 5%; kaolin present in a solid weight fraction amount ranging from 17% to 50%; and optionally Ball Clay in a solid weight fraction amount ranging from 0% to 25%. Although makeable by other processes, in some embodiments, the composition is makeable by mixing component ingredients. Although usable for other purposes, in some embodiments, the composition is used to make ceramic pieces, e.g., via casting, pressing, jiggering or jollying, especially when the slip has solids, chemistry and viscosity suitable for shaping before drying, sintering, and optionally finishing.

FIELD

A composition which comprises at least one form of attapulgite presentin a solid weight fraction amount ranging from 0.25% to 5%; kaolinpresent in a solid weight fraction amount ranging from 17% to 50%; andoptionally Ball Clay in a solid weight fraction amount ranging from 0%to 25%. Although makeable by other processes, in some embodiments, thecomposition is makeable by mixing component ingredients. Although usablefor other purposes, in some embodiments, the composition is used to makeceramic pieces, e.g., via casting, pressing, jiggering or jollying,especially when the ceramic formulation has solids, chemistry andviscosity suitable for shaping before drying, sintering, and optionallyfinishing.

A composition, in the form of powder(s), granules or prills; or in theform of a slurry; or in the form of a paste or filter cake that can beused to prepare a suspension, slip, or a pug which can be cast, pressed,jiggered or jollied into ceramic pieces, containing reducedconcentration of, or no, Ball Clay, along with at least one kaolin, atleast one form of attapulgite; ground quartz; ground feldspar, alongwith addition of dispersants and other additives. Although usable forother purposes, the composition is usable to prepare a slip or pug tocast, press, jigger or jolly ceramic pieces. Although makeable in otherways, the composition is makeable by blending the kaolin, the at leastone form of attapulgite, and Ball Clay in the form of crude clay, driedclay, or slurried clay, or any combination of these, along with additionof quartz, feldspar, dispersants and other additives.

A composition, in the form of a ceramic body, with or without finishing,that has been cast, pressed, jiggered or jollied to form a ceramic pieceusing the inventions described. Introduction

Ball Clays are a group of clays comprised of 20% to 80% kaolinite, 10%to 25% mica, 6% to 65% quartz and a variety of other minerals andcarbonaceous materials (such as lignite) in smaller ratios. Because theywere deposited in layers over time, there are sometimes largedifferences in mineral and chemical composition within a single deposit.

Ball Clays are used in ceramics for their plasticity.

Ball Clays are used in slips because of their ability to suspend highdensity minerals in slurries and slips.

Ball Clays are rare, being mined primarily in Kentucky, Tennessee,Mississippi and parts of England.

One disadvantage of Ball Clay is difficulty reaching a stable viscosity,without aging Ball Clay slurry for one to seven days prior to productionof a full slip.

One disadvantage of Ball Clay is difficulty controlling casting rate ofa slip to achieve a rapid casting.

One disadvantage of Ball Clay is difficulty in obtaining local sourcesin many parts of the world, raising the cost of ceramics produced withBall Clay.

One disadvantage of using Ball Clay is the need to use 3 to 4 differentBall Clays along with 2 to 3 different kaolin clays to balance all theproperties required of the plastic portion of a body formulation.

One difficulty replacing Ball Clay is maintaining plasticity, especiallyin cast and dry pieces (green strength) without affecting viscositybuild and casting rate of the slip.

One difficulty replacing Ball Clay is maintaining fired strength withoutlosing plasticity (green strength) or changing the percent shrinkage ofa fired piece.

It is to be understood that both the foregoing general description andthe following detailed description are representative and explanatoryonly and are not restrictive of the invention, as claimed.

The accompanying tables in the drawings, which are incorporated in andconstitute a part of this specification, illustrate embodiments of theinvention and together with the description, serve to explain theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description, serve to explain the principles of theembodiments described herein.

FIG. 1 shows a component key.

FIG. 2 shows a SWF for components of embodiments.

FIG. 3 shows a comparison of theoretical and measured values ofobservables.

FIG. 4 shows a comparison of slips made without Ball Clay.

FIG. 5 shows properties of ceramic pieces.

DESCRIPTION OF THE EMBODIMENTS

The percent solids by weight (w/w %) is the weight of dry solids in agiven volume of a composition divided by the total weight of thecomposition multiplied by 100%. w/w % is calculated using the followingformula:

w/w%=W _(s) /W _(t)×100%  (1)

in which W_(s) is the weight of dry solids in the composition, and W_(t)is the total weight of the composition. For example, if the total weightof solids (W_(s)) in a composition is 75 g, and the total weight ofcomposition (W_(t)) is 100 g, then the percent solids by weight w/w % is75%.

The percent solid weight fraction of an ingredient of a composition(SWF_(i)%) is the weight of the dry solid ingredient in a given volumeof the composition divided by the total dry weight of all solids in thatvolume of the composition multiplied by 100%. The formula is:

SWF _(i)%=W _(s,i) /W _(s)×100%  (2)

in which W_(s,i) is the weight of the dry solid ingredient in thecomposition having total weight W_(s). For example, if the total weightof solids (W_(s)) in a composition is 100 g, and 2.0 g of which isActiGel®208 (W_(s,i)), then for ActiGel®208, SMF_(ActiGel®208)%=2.0%.

A composition comprises at least one form of attapulgite present in asolid weight fraction amount ranging from 0.25% to 5%; kaolin present ina solid weight fraction amount ranging from 17% to 50%; and optionallyBall Clay in a solid weight fraction amount ranging from 0% to 25%.

In some embodiments, the at least one form of attapulgite from alocality chosen from Palygorskaya, near the Popovka River, Perm, Russia;Attapulgus, Decatur Co., Georgia; at Tafraout, Morocco; and in theHyderabad deposit, Andhra Pradesh, India. In some embodiments, theattapulgite is from Attapulgus, Decatur Co., Georgia. In someembodiments, the attapulgite is associated with other non-attapulgiteminerals, such as montmorillonite, dolomite, calcite, talc, chlorite,quartz, and the like. In some embodiments, the attapulgite issubstantially free of non-attapulgite minerals and is a purified hydrousmagnesium alumino silicate. Such purified attapulgite (hydrous magnesiumalumino silicate) is, in some embodiments, available by using themethods in U.S. Pat. Nos. 6,444,601 and 6,130,179, each of which isincorporated herein in its entirety.

In some embodiments, the attapulgite is a purified hydrous magnesiumalumino silicate.

In some embodiments, the at least one form of attapulgite is chosen fromattapulgites impoverished in smectite. Such impoverishment, in someembodiments, is obtained by dry processing. In some embodiments, the atleast one form of attapulgite is from a dry-processed,finely-pulverized, gelling grade of bulk Mg-aluminosilicate clay chosenfrom the fuller's earth deposits in the Meigs-Quincy district nearAttapulgus, Ga. For example, in some embodiments, the dry-processedattapulgite has not been purified for removal of smectite.

In some embodiments, the dry processed attapulgite is chosen fromMIN-U-GEL® 200, MIN-U-GEL® 400, MIN-U-GEL® G-35, FG, FLORIGEL® HY, andMIN-U-GEL® MB. Each is available from Active Minerals International.

Attapulgite is sometimes referred to as salt gel or fuller's earth. Insome embodiments, attapulgite is a hydrous magnesium aluminum-silicateproduced in gel and absorbent grades.

In some embodiments, the attapulgite is MIN-U-GEL® or Florigel®.

In some embodiments, the one or more forms of attapulgite is MIN-U-GEL®and ACTI-GEL® 208.

In some embodiments, the at least one attapulgite is Liquid Acti-Gel®208 or a slurry of attapulgite chosen from the fuller's earth depositsin the Meigs-Quincy district near Attapulgus, Ga.

In some embodiments, the one or more forms of attapulgite are added inthe form of a slurry or pre-gel, consisting of the one or more forms ofattapulgite and water. In some embodiments, the pre-gel consists of from18% to 26% (w/w %) of the one or more forms of attapulgite by weight andthe remainder water.

In some embodiments, the at least one attapulgite is unprocessed crudeclay chosen from the fuller's earth deposits in the Meigs-Quincydistrict near Attapulgus, Ga.

In some embodiments, the at least one form of attapulgite is chosen frompurified attapulgites, such as those noted herein, and dry processedattapulgites, such as those noted herein.

In some embodiments, the composition further comprises at least onesecond form of attapulgite present in an amount SWF ranging from 1% to4.5%. For example, the amount of the at least one second form ofattapulgite ranges from 1% to 4% or from 0.5% to 2%. When one secondform of attapulgite is used its SWF is in addition to the SWF of the atleast one form of attapulgite.

In some embodiments, the at least one second form of attapulgite ischosen from dry processed attapulgites, such as those noted herein.

In some embodiments, the at least one form of attapulgite is present inan amount SWF ranging from 1.0% to 5.0% or from 0.5% to 4.0% or from0.25% to 2.0%.

In some embodiments, kaolin clay is chosen from inert hydrous aluminumsilicate clay with MBI less than 5 (See ASTM C-837-09), and grit contentless than 1%. In some embodiments, the kaolin is chosen from those inwhich less than or equal to 0.25 wt % of the material has a size greaterthan 47 μm or less than or equal to 0.12 wt % of the material has a sizegreater than 47 μm. In some embodiments, kaolin clay is chosen frominert hydrous aluminum silicate clay with MBI 7 to 15 or MBI 12 to 25.

In some embodiments, kaolin clay is chosen from inert hydrous aluminumsilicate clay with a low surface area.

In some embodiments, kaolin clay is chosen from inert hydrous aluminumsilicate clay with Baroid casting rate above 200 g and surface areabelow 10 m²/g.

In some embodiments, the kaolin clay is chosen from crude, unprocessedkaolin in which less than 6% has a size greater than 47 μm.

In some embodiments, the kaolin clay is chosen from air float kaolinclays such as those obtained from Active Minerals InternationalActi-Min® line of air-floated kaolin clays.

In some embodiments, the kaolin clay is chosen from hard and soft clays.In some embodiments, the soft clay is air float kaolin. In someembodiments, the hard clay is reinforcement clay.

In some embodiments, the kaolin clay is chosen from ACTI-MIN® SA-1,ACTI-MIN® CR, ACTI-MIN® WC-5, ACTI-CAST® CM, ACTI-CAST® Coarse,ACTT-CAST® AF, ACTI-MIN® RP-2, ACTI-MIN® RP-80, ACTI-MIN® S1-R,ACTI-MIN® FE, CHAMPION®, and CROWN®.

In some embodiments, the kaolin is present in an amount SWF ranging from32% to 38% or from 35% to 40% or from 38% to 48%.

In some embodiments, the Ball Clay is chosen from one or more sources inKentucky, Tennessee and Mississippi.

In some embodiments, the Ball Clay is present in an amount SWF rangingfrom 2% to 17% or from 1% to 5.0% or from 7% to 15%.

In some embodiments, the composition further comprises at least oneliquid. In some embodiments, the at least one liquid is water. In someembodiments, the liquid comprises water and at least one other liquid.In some embodiments, the water is present in an amount greater than 80%v/v relative to the total volume of the water plus the volume of the atleast one other liquid. In some embodiments, the amount is greater than90% v/v or 95% v/v or 99% v/v. In some embodiments, the amount rangesfrom 85% to 95% v/v or from 96% to 99% v/v.

In some embodiments, the at least one other liquid is an organic liquid.In some embodiments, the at least one other liquid is miscible withwater or at least partially miscible with water. In some embodiments,the at least one other liquid is an alcohol.

In some embodiments, the composition further comprises quartz orfeldspar.

In some embodiments, the Quartz is crystalline silica having a D90 ofless than 75 μm or less than 45 μm. In some embodiments, the silica ischosen from quartz sand, sandstone, or flint pebbles.

In some embodiments, the Feldspar is sodium feldspar having a D90 ofless than 75 μm or less than 45 μm. In some embodiments the Feldspar maybe substituted with potassium feldspar, nepheline syenite or aplite. Insome embodiments, the feldspar is chosen from aluminosilicatescontaining sodium (Na), potassium (K), and/or calcium (Ca).

In some embodiments, the composition further comprises a dispersant. Insome embodiments, the dispersant is organic, such as polyacrylates andacrylic derivatives or polycarbonates. In some embodiments, thedispersant is inorganic, such as sodium silicates, phosphates andpolyphosphates, sodium and potassium hydroxides, and sodium andpotassium carbonates. In some embodiments, the dispersant is chosen fromsodium silicate, tripolyphosphate pyrophosphate, tetraphosphate, andesametaphosphate. In some embodiments, the dispersant is chosen fromtetrasodium pyrophosphate TSPP. In some embodiments, the composition isfree of dispersant.

In some embodiments, the composition comprises additives, other thanthose noted above. In some embodiments, these additives are chosen fromdispersants, surfactants, binders, coagulants, flocculants and pHmodifiers.

In some embodiments, the composition further comprises dispersants suchas those chosen from sodium silicate, tripolyphosphate pyrophosphate,tetraphosphate, and esametaphosphate disperants. The dispersant ispresent in an amount sufficient to maintain low viscosity at high solidscontent. In some embodiments, the dispersant is tetrasodiumpyrophosphate TSPP.

In some embodiments, the composition further comprises one or morequaternary amines. In some embodiments, the one or more quaternaryamines make it possible to maintain plasticity and increase cast rate,or to counteract the effects of high dispersant concentration.

Quaternary amines are commonly used as industrial and householddisinfectants, or as surfactants, fabric softeners and anti-staticagents, or in cosmetics and personal care items such as shampoos. Theyhave not been used in the ceramic industry for control of casting rateand plasticity.

In some embodiments, the one or more quaternary amines are chosen fromthose of the following formula:

[N—R₁R₂R₃R₄]⁺X⁻,in which

N is nitrogen,

R₁-R₄ are independently chosen from C₁-C₅₀ alkyl groups (such as C₁(methyl), C₂ (ethyl), C₃ (i-propyl or n-propyl), C₄, C₅, C₆, C₈, C₁₀,C₁₂, C₁₄, C₁₆, and C₁₈ and longer alkyl chains with up to 50 carbons) oran aryl group having from 6 to 14 carbon atoms and optionally linkedwith an alkyl spacer having C₁-C₁₈ (such as phenyl, benzyl, ethylphenyl, C₃-C₁₈ phenyl), and

X— is an anion, such as chloride, bromide, acetate and saccharinate.

In some embodiments, R₁-R₄ are the same. In some embodiments, R₁-R₄differ. In some embodiments, some of R₁-R₄ are the same while otherdiffer.

In some embodiments, the quaternary amines are chosen from those of theabove formula in which R₁ is benzyl, R₂ and R₃ are methyl and R₄ isC₈-C₁₈, and optionally still X⁻ is chloride.

In some embodiments, the quaternary amines are benzalkonium chloride, ordistearyl dimethyl ammonium chloride or n-alkyl dimethyl benzylchloride.

In some embodiment, the quaternary amines are chosen frombabassuamidopropalkonium chloride, benzalkonium chloride, benzathoniumchloride, grapefruit seed extract, methylbenzethonium chloride,cetalkonium chloride, vegetable oil quaternary, quaternium-15,stearalkonium chloride, polyquaternium, guar hydroxypropyltrimoniumchloride, behentrimonium chloride, behentrimonium methosulfate.

Quaternary amines make it possible, in some embodiments, to increasecast rate of the composition from 50% to 150%.

Quaternary amines make it possible, in some embodiments, to allow forthe composition to be fully dispersed to a low viscosity using organicor inorganic dispersants, or both types of dispersants, and then to berecovered to an acceptable casting rate and high plasticity.

Quaternary amines make it possible, in some embodiments, to bring ameasure of plasticity, as determined by ease of cutting an object, intothe same range as observed when cutting a traditional ball clay slip.

The composition, in some embodiments, to, when cast at high pressure,firms up sufficiently to be cut within minutes of removing from themold.

When present, the one or more quaternary amines are present in a solidweight fraction (SWF) amount ranging from 0.005 to 0.025% or from 0.01to 0.04% or from 0.02 to 0.5%.

In some embodiments, the composition further comprises one or morecoagulants, such as inorganic coagulants or organic coagulants or acombination of both inorganic and organic coagulants. In someembodiments, the organic coagulants are chosen from polyamines,polyDADMAC, melamine formaldehyde, and tannins. In some embodiments, theinorganic coagulants are chosen from aluminum sulfate (alum), aluminumchloride, polyaluminum chloride (PACl), aluminum chlorohydrate (ACH),ferric sulfate, ferrous sulfate, and ferric chloride.

In some embodiments, the composition further comprises one or moreflocculants, such as cationic or anionic flocculants. In someembodiments, the cationic flocculants are chosen from polymers andcopolymers, such as copolymers of AETAC (N,N-dimethylaminoethyl acrylatemethyl chloride quaternary) or METAC (N,N-dimethylaminoethylmethacrylate methyl chloride quaternary) and acrylamide. In someembodiments, the anionic flocculants are chosen from polymers andcopolymers, such as copolymers of acrylamide and acrylic acid.

In some embodiments, the composition further comprises one or more pHmodifiers. In some embodiments, the pH modifier is selected from gypsum,hydrated lime, ammonium nitrate, and aluminum sulfate. In someembodiments, the pH modifier is chosen from sodium hydroxide, causticsoda, hydrated lime, shell meal, limestone, burned lime, dolomite, sugarbeet lime, and calcium silicate. In some embodiments, the pH modifier ischosen from aluminum sulfate, calcium sulfate, magnesium sulfate, Epsomsalt, calcium chloride, lime sulfur, ferric sulfate, sulfuric acid,acetic acid, hydrochloric acid, sulfur, and gypsum. In some embodiments,the neutralizer is selected from gypsum, hydrated lime, ammoniumnitrate, and aluminum sulfate.

In some embodiments, the composition is in a form chosen from aqueoussuspensions or slurries, pugs, pastes, cakes, powders, granules,pellets, and prills.

As used herein, a suspension or slurry is a paste or liquid in whichsolid particles are partially or fully dispersed.

As used herein, a suspension is a liquid in which solid particles aredispersed. A slurry is a flowable suspension.

As used herein, a slip is a liquid in which substantially all thecomponents of a ceramic body have been mixed. The solid particles of aslip or suspension are the solid particulates.

In some embodiments of an aqueous suspension, the liquid is water. Insome embodiments, the liquid comprises water and at least one otherliquid. In embodiments of an aqueous suspension, the water is present inan amount greater than 80% v/v relative to the total volume of the waterplus the volume of the at least one other liquid. In some embodiments,the amount is greater than 90% v/v or 95% v/v or 99% v/v. In someembodiments, the amount ranges from 85% to 95% v/v or from 96% to 99%v/v.

In some embodiments, the aqueous suspension is a slurry, i.e., flowable.

As used herein, a slip is a liquid in which substantially all thecomponents of a ceramic body have been mixed. The solid particles of aslip or suspension are the solid particulates.

In some embodiments, the aqueous suspension has a total percent solidsby weight (w/w %) amount ranging from 60% to 74% or from 65% to 75%.

In some embodiments, the composition is in the form chosen from pugs orpastes. For example, the composition is mixed with water (as notedherein) and optionally at least one other liquid (as noted herein) tomake a workable paste in a pug mill, before an optional extrusion.

In some embodiments, the composition has a form chosen from pugs, pastesor cakes having a total percent solids by weight (w/w %) amount rangingfrom 70% to 90% or from 75% to 85%.

In some embodiments, the composition is in the form of a pug having atotal percent solids by weight (w/w %) amount ranging from 75% to 90%(w/w %) solids.

In some embodiments, the composition has a form chosen from powders,granules, pellets, and prills having a total percent solids by weight(w/w %) amount ranging from 85% to 100%.

The composition is makeable by mixing. In some embodiments, theingredients of the composition are mixed. In some embodiments, mixing isfacilitated by a mixer, such as a dry mixer such as a ribbon mixer, acement mixer, a Mueller mixer, and the like.

In some embodiments, the ingredients of the composition are agitated toform a composition in the form of an aqueous slurry or suspension.

In some embodiments, the composition in the form of pug, cake, powder,granule, pellet or prill is mixed in water first, followed by additionof the non-plastic materials, if desired, and other materials; in someembodiments, the composition in the form of pug, cake, powder, granule,pellet or prill is added second or last. In some embodiments, thecomposition is not aged after addition to water or slurry. Order ofaddition is variable.

In some embodiments, the composition in the form of a slurry is notaged; in some embodiments, the composition in the form of a slurry isreduced in solids concentration (w/w %) prior to addition of othermaterials; in some embodiments, the composition in the form of a slurryis added to a slurry or paste of other materials. Order of addition isnot critical.

In some embodiments, the composition is prepared by adding the one ormore forms of attapulgite, the kaolin and the Ball Clay in the form ofpowder clay, a liquid or slurry, or crude unprocessed clay. In someembodiments the dispersant and other materials are added in the form ofa liquid or slurry.

In some embodiments the composition is in the form of slurry. Forexample, the method of making the composition, in the form of a slurry,comprises mixing water, the at least one form of attapulgite, kaolin,Ball Clay, dispersant and other materials, and mixing to form ahomogeneous composition at a viscosity below 1500 cP, or between 1600and 2500 cP, or between 1200 and 1800 cP. In some embodiments, themixing further comprises mixing a second form of attapulgite, and thecomposition in the form of slurry comprises at least one second form ofattapulgite.

These are exemplary methods of making, and any composition describedherein is makeable by mixing the ingredients and agitating describedherein.

In some embodiments, the composition is prepared by adding theingredients to a pug mixer to form a pug, paste or granules.

In some embodiments, the composition is prepared by producing slurryfollowed by filter pressing to make a press cake, or followed by spraydrying to make granules, or followed by pin mixing to make granules.

In some embodiments, the storage of the composition in the form ofslurry is for a period greater than 8 hours. In some embodiments, thestorage is for a period ranging from 8 hours to 7 days. In someembodiments, the storage is for a period ranging from 3 to 6 days orfrom 4 to 5 days. In some embodiments, the storage is for 6 to 10 weeksduring transport.

In some embodiments the slurry viscosity is altered by addition ofdispersant after storage.

FIG. 1 contains Table 1, which gives the Key to abbreviations ofcomponents in Tables 2-5.

FIG. 2 contains Table 2, which shows the components of three formulasalong with the resulting proportions of Plastic and non-Plasticcomponents. Each component was measured by X-Ray Fluorescence (XRF) formain oxide chemistry; LOI was determined at 1000° C. and soluble SO₄ wasdetermined by light transmission using a Hach meter.

A proprietary software model that uses the chemistry of the individualcomponents to predict the chemistry of the full formula was used tocompare measured oxide values to predicted oxide values.

FIG. 3 contains Table 3, which compares the chemical analysis predictedby the proprietary software of the three formulas in FIG. 2's Table 2 tothe chemical analysis (XRF) as measured by an independent laboratory.Based on this comparison, oxide values predicted by the proprietarysoftware are considered reasonable substitutes for measured values.

FIG. 4 contains Table 4, which compares slip properties of variousformulas, all of which are predicted by the inventors to havechemistries similar to each other, as demonstrated by the three formulasin Table 3. Properties include Surface Area of the dry blend in m²/gmeasured by single point BET; Viscosity of a 74% (w/w %) solids slipmeasured with a #2 Brookfield spindle at 10 RPM; the concentration ofsodium silicate (SWF) of the dry blend at the tested viscosity; theBaroid cake weight in grams after pressure filtering the slip (a measureof casting rate).

For example, similar viscosity was achieved with Formulas ATTA 3 and Y-1compared to Control A, but dispersant demand was significantly lower andcasting rate as indicated by Baroid was significantly higher.

The composition is useable to make ceramic pieces.

In some embodiments, the composition is formed into wet ceramic pieceshaving defined shapes. For example, a base composition is wet with waterand optionally one other liquid until a desired level of viscosity,plasticity and moldability is attained (slip or slurry options maycontain e.g., dispersants). In some embodiments, the wet ceramic pieceshaving defined shapes are formed by extruding the composition. In someembodiments, the wet ceramic pieces having defined shapes are formed bypressing the composition. In some embodiments, the wet ceramic pieceshaving defined shapes are formed by jiggering and/or jollying thecomposition. In some embodiments, the wet ceramic pieces having definedshapes are formed by casting the composition.

In some embodiments, the wet ceramic pieces having defined shapes aredryable to form a dried ceramic piece. In some embodiments, the wetceramic pieces having defined shapes are dried to form a dried ceramicpiece using tunnel drying or periodic drying.

In some embodiments, the dried ceramic pieces are sinterable via heat toform a ceramic piece. Sintering results in densification. In someembodiments, sintering via heat is accompanied by compressing the driedceramic piece before sintering via heat.

The ceramic pieces are finishable. In some embodiments, the ceramicpieces are finished by lapping, grinding, polishing, and/or glazing. Insome embodiments, the ceramic pieces are finished by lapping, grinding,and/or polishing.

In some embodiments glaze is applied before sintering and must shrink ata rate similar to that of the body during the sintering process toprevent cracking or crazing.

FIG. 5 contains Table 5, which compares properties of rods cast ingypsum molds of various formulas, all of which are predicted by theinventors to have similar chemistries as demonstrated by the threeformulas in FIG. 3's Table 3. Properties include Green MOR and FiredMOR, both measurements of strength in psi at stages in the curing cycle;green shrinkage, and total shrinkage (sum of green and fired shrinkage).

For example, formulas T-M and X-7 provide higher green and firedstrength compared to standard with marginally higher shrinkage.

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byblending a slurry capable of replacing some or most of the plastic andnon-plastic components in a slip for casting.

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byblending a slurry capable of replacing some or most of the plastic andnon-plastic components in a ceramic pug suitable for pressing, jiggeringor jollying

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byforming a pug or cake capable of replacing some or most of the plasticand non-plastic components in a slip for casting.

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byforming a pug or cake capable of replacing some or most of the plasticand non-plastic components in a ceramic pug suitable for pressing,jiggering or jollying.

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byforming a powder, granule, pellet or prill capable of replacing some ormost of the plastic and non-plastic components in a slip for casting.

A composition comprising kaolin, Ball Clay, the at least one form ofattapulgite, quartz and/or feldspar, in some embodiments is makeable byforming a powder, granule, pellet or prill capable of replacing some ormost of the plastic and non-plastic components in a ceramic pug suitablefor pressing, jiggering or jollying.

A composition, in the form of a powder, a granule or a prill having 90%to 100% (w/w %) solids; or in the form of a slurry having 60% to 78%(w/w %) solids; or in the form of a pug having 75% to 85% (w/w %) solidswhich, by replacing some or most of the plastic and non-plasticcomponents of a slip, makes it possible to exhibit reduced agingrequirements.

A composition, in the form of a powder, a granule or a prill having 90%to 100% (w/w %) solids; or in the form of a slurry having 60% to 78%(w/w %) solids; or in the form of a pug having 75% to 85% (w/w %) solidswhich, by replacing some or most of the plastic and non-plasticcomponents of a slip, makes it possible to exhibit greater stability inviscosity and thixotropy.

A composition, in the form of a powder, a granule or a prill having 90%to 100% (w/w %) solids; or in the form of a slurry 60% to 78% (w/w %)solids; or in the form of a pug having 75% to 85% (w/w %) solids which,by replacing some or most of the plastic and non-plastic components of aslip, makes it possible to exhibit equal or greater casting ratescompared to a traditional slip.

As known to the inventors, traditional slips and pugs comprise a plasticportion that includes Ball Clay and kaolin in a ratio of approximately2:1; e.g., SWF of 30%:15%; or 34%:16% or; 37%:15%, along with other clayminerals and dispersants.

As known to the inventors, traditional slips and pugs comprise anon-plastic portion that includes ground silica and ground feldspar in aratio of approximately 3:7; e.g., SWF of 11%:38%; or 10%:40%; 12%:42%,along with other minerals and additives.

As known to the inventors, traditional slips and pugs comprise plasticto non-plastic ratio of approximately 1:1; e.g., Plastic to non-plasticSWF ratio of 51%:49%; or 50%:50%; or 52%:48%; or 48%:52%, along withsmall additions of dispersants, additives and other plastic ornon-plastic minerals.

All solids in a slip are present in solids fraction of approximately 65%to 75% (w/w %). Applications of a slip include, but are not limited to,casting sanitaryware, electrical porcelain and certain types oftableware.

All solids in a pug or cake are present in solids fraction ofapproximately 75% to 85% (w/w %). Applications include, but are notlimited to pressed tile and craft ware.

A composition comprising kaolin, Ball Clay, and the at least one form ofattapulgite, in some embodiments, is a blended slurry capable ofreplacing some or the entire plastic component in a slip for casting.

A composition comprising the at least one form of attapulgite, kaolinand Ball Clay, in some embodiments, is a blended slurry capable ofreplacing some or the entire plastic component in a ceramic pug suitablefor pressing, jiggering or jollying.

A composition comprising the at least one form of attapulgite, kaolinand Ball Clay, in some embodiments, is a pug or cake capable ofreplacing some or the entire plastic component in a slip for casting.

A composition comprising the at least one form of attapulgite, kaolinand Ball Clay, in some embodiments, is a pug or cake capable ofreplacing some or all of the plastic component in a ceramic pug suitablefor pressing, jiggering or jollying.

A composition comprising the at least one form of attapulgite, kaolinand Ball Clay, in some embodiments, is a powder, granule, pellet orprill capable of replacing some or all of the plastic component in aslip for casting.

A composition comprising the at least one form of attapulgite, kaolinand Ball Clay, in some embodiments, is a powder, granule, pellet orprill capable of replacing some or all of the plastic component in aceramic pug suitable for pressing, jiggering or jollying.

A composition in the form chosen from powders, granules, and prillshaving 90% to 100% (w/w %) solids; or in the form of a slurry having 60%to 78% (w/w %) solids; or in the form of a pug having 75% to 85% (w/w %)solids which, by replacing the plastic component of a slip makes itpossible (1) to reduce aging requirements; (2) to exhibit greaterstability in viscosity and thixotropy; and/or (3) to exhibit equal orgreater casting rates compared to a traditional slip.

Other embodiments of the invention will be apparent to those of ordinaryskill in the art from consideration of the specification and practice ofthe embodiments disclosed herein. It is intended that the specificationand examples be considered as non-limiting, with a true scope and spiritof the invention being indicated by the following claims.

1. A composition, comprising: one or more quaternary amines; at leastone form of attapulgite present in a solid weight fraction (SWF) amountranging from 0.25% to 5%; kaolin present in a solid weight fraction(SWF) amount ranging from 17% to 50%; and Ball Clay present in a solidweight fraction (SWF) amount ranging from 0% to 25%.
 2. The compositionof claim 1, wherein the at least one form of attapulgite is present inan amount SWF ranging from 0.5% to 4.0%.
 3. The composition of claim 1,wherein the at least one form of attapulgite is chosen from attapulgitesimpoverished in smectite.
 4. The composition of claim 1, wherein the atleast one form of attapulgite is chosen from purified attapulgite anddry processed attapulgite.
 5. The composition of claim 1, wherein the atleast one form of attapulgite is chosen from attapulgite slurry orunprocessed crude attapulgite.
 6. The composition of claim 1, whereinthe kaolin is present in an amount SWF ranging from 35% to 45%.
 7. Thecomposition of claim 1, wherein the total percent solids by weight (w/w%) amount in the composition ranges from 60% to 99%.
 8. The compositionof claim 1, further comprising at least one second form of attapulgitepresent in an amount SWF ranging from 0.25% to 4%.
 9. The composition ofclaim 8, wherein the at least one form of attapulgite is chosen frompurified attapulgite; and wherein the at least one second form ofattapulgite is chosen from dry processed attapulgite, unprocessed crudeattapulgite or attapulgite slurry.
 10. The composition of claim 1,wherein the composition is in a form chosen from aqueous slurries,suspensions, pugs, pastes, cakes, powders, granules, pellets, andprills.
 11. The composition of claim 1, wherein the composition has aform chosen from aqueous suspensions having a total percent solids byweight (w/w %) amount ranging from 60% to 74%.
 12. The composition ofclaim 1, wherein the composition has a form chosen from pugs, cakes andpastes having a total percent solids by weight (w/w %) amount rangingfrom 70% to 90%.
 13. The composition of claim 1, wherein the compositionhas a form chosen from powders, granules, pellets, and prills having atotal percent solids by weight (w/w %) amount ranging from 85% to 100%.14. A method of making a composition, comprising mixing one or morequaternary amines, at least one form of attapulgite, kaolin, andoptionally Ball Clay, wherein the composition comprises: one or morequaternary amines; at least one form of attapulgite present in a solidweight fraction (SWF) amount ranging from 0.25% to 5%; kaolin present ina solid weight fraction (SWF) amount ranging from 17% to 50%; and BallClay present in a solid weight fraction (SWF) amount ranging from 0% to25%.
 15. The method of claim 14, comprising mixing one or morequaternary amines, a liquid, at least one form of attapulgite, kaolin,and optionally Ball Clay to make a mixture.
 16. The method of claim 15,wherein the liquid comprises water.
 17. The method of claim 16, whereinthe mixture is agitated to form a slurry or suspension, and thecomposition is in the form of an aqueous slurry or suspension.
 18. Themethod of claim 15, wherein the liquid further comprises at least oneorganic liquid. 19.-20. (canceled)
 21. The method of claim 14, furthercomprising mixing one or more ingredients selected from silica,feldspar, and nepheline syenite with the one or more quaternary amines,at least one form of attapulgite, kaolin, and optionally Ball Clay. 22.The composition of claim 1, further comprising one or more ingredientsselected from silica, feldspar, and nepheline syenite.